Area Forecast Discussion
Issued by NWS Wilmington, NC

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000
FXUS62 KILM 101843
AFDILM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
243 PM EDT THU JUL 10 2014

.SYNOPSIS...
A COLD FRONT WILL STALL ACROSS THE REGION TONIGHT...PERSISTING
INTO EARLY SATURDAY. THIS WILL BRING GOOD CHANCES FOR
THUNDERSTORMS THE NEXT FEW DAYS...WITH PERIODS OF HEAVY RAINFALL.
THIS FRONT WILL DISSIPATE LATE IN THE WEEKEND WITH A RETURN TO
TYPICAL SUMMERTIME CONDITIONS...WITH A WARMING TREND DEVELOPING
EARLY NEXT WEEK. ANOTHER COLD FRONT WILL APPROACH ON WEDNESDAY.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 200 PM THURSDAY...SEVERE THUNDERSTORM WATCH ISSUED FOR
NORTHEAST SOUTH CAROLINA INTO EASTERN PORTIONS OF NORTH CAROLINA
THROUGH 9 PM THIS EVENING. THE GREATEST THREAT WILL BE POTENTIAL
FOR DAMAGING WIND GUSTS. ALTHOUGH BRUNSWICK...NEW HANOVER AND
PENDER COUNTIES REMAIN IN THE WATCH...THERE IS SOME QUESTION AS TO
THE RECOVERY OF THE ATMOSPHERE AFTER BEING WORKED OVER WITH
CONVECTION EARLY TODAY. THE MAIN FOCUS FOR SVR POTENTIAL WILL
ACTUALLY REMAIN TO THE NORTH OF LOCAL AREA BUT AS UPPER TROUGH
SHIFTS EAST...HEIGHT FALLS AND BETTER JET DYNAMICS WILL CONTRIBUTE
TO STRONGER STORMS OVER LOCAL AREA. VERY MOISTURE RICH AIR LIES
AHEAD OF THE FRONT WITH PCP WATER VALUES UP CLOSE TO 2 INCHES. MU
CAPE VALUES REACH UP AROUND 2000 J/KG. LAPSE RATES REMAIN FAIRLY
NEUTRAL WITH LESS OVERALL HEATING IN MOST PLACES LIMITING THE
CONVECTION POTENTIAL BUT CLOUD FREE AREA WILL CONTINUE TO HEAT UP
HELPING TO DESTABILIZE ATMOSPHERE. THE BEST CONVERGENCE WILL
BE ALONG AND JUST AHEAD OF COLD FRONT BUT LINGERING BOUNDARIES
FROM CONVECTION THIS MORNING ALONG WITH CONVERGENCE ALONG SEA
BREEZE BOUNDARY AND DIFFERENTIAL HEATING WILL HELP TO INITIATE
STORMS. WITH A STORM MOTION OUT OF THE SOUTHWEST AT 10 MPH...SOME
TRAINING OF CELLS COULD PRODUCE POTENTIAL FOR FLOODING THROUGH
THIS AFTERNOON. ALTHOUGH CELL MOTION WILL BE FROM SOUTHWEST TO
NORTHEAST...THE STORMS WILL SHIFT EASTWARD THROUGH TIME AS UPPER
LEVEL TROUGH PUSHES FRONT SLOWLY EAST.


CLOUDS AND PCP WILL KEEP TEMPS FROM REACHING AS HIGH AS PAST
COUPLE OF DAYS WITH HIGHS OF 85 TO 90 MOST PLACES...BUT SOME SPOTS
EXPERIENCING GREATER SUN WILL END UP INTO THE 90S ESPECIALLY OVER
INLAND SOUTH CAROLINA. THE CLOUDS AND SHWRS WILL KEEP OVERNIGHT
LOWS HIGHER ONCE AGAIN...REMAINING IN THE MID TO UPPER 70S MOST
PLACES. THE COLD FRONT WILL HANG OVER THE AREA TONIGHT WITH
POTENTIAL FOR CONVECTION INTO FRIDAY.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 330 AM THURSDAY...FRIDAY CONTINUES TO LOOK VERY WET LOCALLY AS
ELEMENTS COMBINE TO PRODUCE WIDESPREAD CONVECTION WITH HEAVY RAIN.
AT THE SURFACE...A WEAKENING COLD FRONT WILL BE WAVERING ACROSS THE
CWA...AND THIS...ALONG WITH REMNANT OUTFLOW BOUNDARIES FROM
CONVECTION ON THURSDAY...WILL SERVE AS FOCI FOR UPDRAFTS ON FRIDAY.
ALOFT...SHEAR LINE DEMARCATING THE LONGWAVE TROUGH AXIS WILL SWING
OVERHEAD AND NORTHEAST DURING THE DAY...WHILE 300MB 100KT JET MOVES
OVER NEW ENGLAND...LEAVING THE CAROLINAS WITHIN THE FAVORABLE RFQ
DIFLUENT REGION...IN A SETUP THAT RESEMBLES QUITE WELL A
MADDOX-TYPE EVENT FROM LITERATURE FOR HEAVY RAIN.

ALL THIS OCCURS IN A THERMODYNAMIC ENVIRONMENT CHARACTERIZED BY
SBCAPE OF 800-1000 J/KG...PWATS OVER 2 INCHES...AND WARM CLOUD
DEPTH APPROACHING 11 KFT. THE "LONG SKINNY" CAPE PROFILE SUGGESTS
EFFICIENT PRECIPITATION PROCESSES (LONGER PARCEL RESIDENCE TIMES
WITHIN STRONG COLLISION-COALESCENCE ENVIRONMENT) IN UPDRAFTS
FRIDAY AS WELL...SO ALL SIGNS POINT TO A VERY ACTIVE DAY WITH
HEAVY RAINFALL THE PRIMARY THREAT WITHIN THUNDERSTORMS. ALTHOUGH
DRIER AIR WILL SLOWLY BEGIN TO FILTER INTO THE MID-LEVELS AS AN
EMBEDDED SHORTWAVE PUSHES OFFSHORE LATE FRIDAY...STILL ANTICIPATE
A SIGNIFICANT QPF DAY...HIGHEST EASTERN HALF OF THE CWA. TEMPS
WILL BE TEMPERED BY THE WIDESPREAD CLOUDS AND RAIN...RISING ONLY
INTO THE MID/UPR 80S. LOWS AT NIGHT WILL DROP INTO THE MID 70S AT
THE COAST...BUT AROUND 70 WELL INLAND WHERE DRIER AIR WILL BECOME
MORE PRONOUNCED LATE.

SATURDAY WILL BE A TRANSITIONAL DAY AS RIDGING FROM THE SOUTHWEST
TRIES TO BLOSSOM ACROSS THE AREA. IT WILL GET SHUNTED EAST BY THE
AFOREMENTIONED LONGWAVE TROUGH...BUT THE WESTERLY FLOW BETWEEN THESE
TWO FEATURES WILL HELP TO DRY THE COLUMN FROM FRIDAY. AT THE SAME
TIME...THE SUBTLE THICKNESS INCREASE WILL HELP TO FURTHER ERODE THE
FRONT WHICH SHOULD BECOME INDISTINGUISHABLE ON SATURDAY.
HOWEVER...IT WILL CONTINUE TO HELP DRIVE CONVECTION...ALBEIT IN A
LESS SIGNIFICANT MANNER THAN FRIDAY. STILL ANTICIPATE SCATTERED
TSTMS SATURDAY AREA-WIDE...WITH TEMPS AGAIN JUST BELOW NORMAL IN
THE UPR 80S TO AROUND 90...AND LOWS A FEW DEGREES ABOVE 70.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 330 AM THURSDAY...SEASONABLE CONDITIONS TO BEGIN THE PERIOD AS
RIDGING DEVELOPS ALOFT AND HIGH PRESSURE OFFSHORE RIDGES BACK
TOWARDS THE COAST. MID-LEVEL WESTERLY FLOW WILL CAUSE A RELATIVELY
DRY COLUMN ON SUNDAY...SO ONLY ISOLATED CONVECTION IS
ANTICIPATED...LIKELY LESS THAN CLIMATOLOGICALLY NORMAL. WITH HEIGHTS
BUILDING ALOFT AND RETURN FLOW DEVELOPING...TEMPS SUNDAY WILL WARM
TO SEASONABLE VALUES. THEREAFTER...HEAT WILL SLOWLY BUILD AGAIN
THROUGH TUESDAY THANKS TO SUBTLE THICKNESS INCREASE DOWNSTREAM OF A
LARGE TROUGH ACROSS THE MIDWEST...AND CONTINUED RETURN FLOW AT THE
SURFACE. THIS DRIVES MORE TYPICAL CONVECTION CHANCES
MONDAY/TUESDAY...BEFORE A COLD FRONT APPROACHES AND STALLS ACROSS
THE AREA BY WEDNESDAY. THIS WILL BRING MUCH MORE WIDESPREAD PRECIP
CHANCES FOR THE MIDDLE OF NEXT WEEK...ALONG WITH TEMPERATURES
COOLING BACK TO SEASONABLE LEVELS.

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
AS OF 18Z...SHRA/TSRA EXPECTED TO DEVELOP JUST INLAND OF THE COASTAL
TERMINALS THIS AFTERNOON...AND THERE IS MODERATE TO HIGH CONFIDENCE
THIS ACTIVITY WILL TRANSLATE TOWARDS KFLO/KLBT AS THE AFTERNOON
PROGRESSES. CONVECTION WILL MOVE FROM KFLO/KLBT TO NEAR THE COASTAL
TERMINALS THIS EVENING...BUT COULD RE-DEVELOP AND CONTINUE THROUGH
06Z AT KFLO/KLBT. OVERNIGHT...ADDITIONAL SHRA/TSRA COULD DEVELOP AT
THE COASTAL TERMINALS...BUT CONFIDENCE IS LOW AS TO THE
INTENSITY/COVERAGE.

DUE TO UNCERTAINTIES IN TIMING AND COVERAGE WILL INDICATE MVFR
CONDITIONS WITH CONVECTION...BUT SHORT TERM IFR IS ALMOST CERTAIN TO
OCCUR...ESPECIALLY AT KFLO/KLBT...AND MAY ADD TO TAFS DEPENDING ON
RADAR TRENDS. IFR SHOULD NOT LAST 15-30 MINUTES AT ANY ONE TERMINAL
UNLESS CELLS TRAIN OVER ANY ONE TERMINAL FOR AN EXTENDED PERIOD OF
TIME. MVFR VSBYS IN BR COULD ALSO OCCUR 09-12Z AT KFLO/KLBT. DESPITE
COPIOUS AMOUNTS OF LOW LEVEL MOISTURE CONFIDENCE OF IFR IS LOW DUE
TO CLOUD COVER.

AFTER SUNRISE SHOWERS WILL BE LIKELY AT THE COASTAL TERMINALS WITH
TEMPO MVFR CONDITIONS. LESS ACTIVITY IS EXPECTED AT KFLO/KLBT.

EXTENDED OUTLOOK...A FRONT STALLS OVER THE REGION WITH A DECENT
CHANCE FOR SHRA/TSRA THROUGH SATURDAY MORNING. SHRA/TSRA ARE AGAIN
POSSIBLE MONDAY AND TUESDAY. BRIEF IFR CONDITIONS ARE POSSIBLE IN
THE HEAVIER SHOWERS AND STORMS. OTHERWISE VFR.

&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 200 PM THURSDAY...SOUTHWESTERLY FLOW WILL CONTINUE OVER THE
WATERS THROUGH TONIGHT AS HIGH PRESSURE OVER THE WESTERN ATLANTIC
INTERACTS WITH AN APPROACHING COLD FRONT WELL INLAND. SEAS WILL
REMAIN 2 TO 4 FT MOST WATERS.

SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 330 AM THURSDAY...A WEAKENING COLD FRONT WILL WAVER IN THE
VICINITY THROUGH SATURDAY...LIKELY REMAINING JUST WEST OF THE
COASTAL WATERS DURING THIS PERIOD. THAT LEAVES A WEAK
GRADIENT...AND S/SE WINDS FRIDAY AND SATURDAY AT 10 KTS OR LESS.
LATE SATURDAY THE COLD FRONT WILL WASH OUT...AND AS HIGH PRESSURE
BECOMES DOMINANT OFFSHORE...WINDS WILL VEER TO BECOME MORE
SWLY...REMAINING AROUND 10 KTS. WAVE HEIGHTS WILL BE HIGHEST ON
FRIDAY...THANKS TO WINDS EASING FROM THURSDAY...WITH 3-4 FT SEAS
LIKELY ON A SOUTHERLY WIND CHOP. THESE HEIGHTS WILL DROP TO 1-3 FT
ON SATURDAY ON THE LIGHTER WINDS.

LONG TERM /SUNDAY THROUGH MONDAY/...
AS OF 330 AM THURSDAY...MORE TYPICAL SUMMERTIME PATTERN WILL DEVELOP
LATE IN THE WKND AND EARLY NEXT WEEK AS HIGH PRESSURE OFFSHORE
EXERTS ITS INFLUENCE ACROSS THE COASTAL WATERS. SW WINDS WILL SLOWLY
INCREASE THROUGH THE PERIOD...BECOMING 15-20 KTS LATE MONDAY. THE
COMBINATION OF THESE RISING WINDS AND AN AMPLIFYING GROUND SWELL
WILL DRIVE SEAS UP FROM 2-3 FT SUNDAY...TO 3-5 FT MONDAY...AND
CAUTIONARY STATEMENTS MAY BE NEEDED EARLY NEXT WEEK.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...
NEAR TERM...RGZ
SHORT TERM...JDW
LONG TERM...JDW
AVIATION...MRR
MARINE...






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